topic Multipathing Issue in Operating System - Linux

Multipathing Issue

Jon Gomersall — Wed, 14 Jan 2009 09:16:43 GMT

We have an issue on an RHEL v4 Update 5 server

One of the mpath devices is only showing one path where as the other shows the correct 2 paths.

This server is attached via fibre cards to an HP XP24000 Array..

The example below shows two mpath devices mpath12 is missing a device mpath5 is correct.

mpath12 (360060e8015251d000001251d00003006)
[size=25 GB][features="0"][hwhandler="0"]
\_ round-robin 0 [prio=1][active]
\_ 1:0:0:12 sdad 65:208 [active][ready]

mpath5 (360060e8015251d000001251d00000ce1)
[size=25 GB][features="0"][hwhandler="0"]
\_ round-robin 0 [prio=1][active]
\_ 0:0:0:5 sdf 8:80 [active][ready]
\_ round-robin 0 [prio=1][enabled]
\_ 1:0:0:5 sdw 65:96 [active][ready]

Any ideas on how to track down the issues with mpath12 devices

Re: Multipathing Issue

Steven E. Protter — Wed, 14 Jan 2009 13:53:11 GMT

Shalom,

1) Install the HP PSP package and verify multi path with the hp_rescan utility. Its good at spotting trouble.

2) You may wish to if the path is good explore the possibility of patching RHEL because there may be a multi-path bug in this release. Q&A at Red Hat has not always been the best.

SEP

Re: Multipathing Issue

skt_skt — Thu, 15 Jan 2009 02:36:58 GMT

_ 0:0:0 comes from a diff HBA than _ 1:0:0

So i would guess mpath12 does not visibility thorugh HBA/0:0:0